With the Revolt 4000 offering 4000mAh of power and 2.1 amps of output, this handy little power storage device can recharge a smart phone up to three times. Its bigger brother – the Revolt 9000 – offers double the capacity and with a 2.1 amp output can charge a smart phone up to six times as well as being ideal for use with tablets, DSLR cameras, e-readers and GPS devices.
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